Abstract: There is described a self-propelled railroad track ballast broom machine having a first broom unit operatively mounted at the rear of the machine frame and a second broom unit operatively mounted at the front of the frame. The broom units have substantially cylindrical brooms extending transversely of the railroad track and deflector boxes located forwardly of each of the brooms. The brooms have gaps sufficiently wide, and so spaced apart thereon, as to avoid broom contact with the rail heads in normal tangent track sweeping operations. When the machine enters into track curves, the first broom unit is so far behind the machine rear axle that it is transversely displaced relative to the track center. Compensating transverse movement can be applied to the first broom unit to maintain the broom gaps in line with the rail heads and the ends of the broom in operative engagement with both the track shoulder edges.